1. Field of the Invention
The present invention relates to a display drive device, a display device having this display drive device, a driving control method therefor, and an electronic device having this display device.
2. Description of the Related Art
In recent years, a light emitting element-type display device having a display panel (pixel array) arranged with light emitting elements in a matrix form has drawn attention as a next-generation display device, successor to a liquid crystal display device. Known examples of such light emitting elements include current-driven light emitting elements such as an organic electroluminescent element (organic EL element), an inorganic electroluminescent element (inorganic EL element), and a light emitting diode (LED).
A light emitting element-type display device using an active matrix-type drive method has a higher display response speed than a well-known liquid crystal display device, and hardly has any field angle, dependency, thus having excellent display characteristics capable of achieving high brightness, high contrast, high resolution of display quality, and the like. Unlike the liquid crystal display device, the light emitting element-type display device does not need any back light or light guiding plate, thus having extremely excellent characteristics that enable itself to be thinner and lighter than ever before. Therefore, the light emitting element-type display device is expected to be applied to various electronic devices in the future.
For example, an organic EL display device as described in Jpn. Pat. Appln. KOKAI Publication No. H8-330600 is known as such light emitting element-type display device. In this organic EL display device, a circuit including a current control thin film transistor for passing a current to an organic EL element serving as a light emitting element and a switch thin film transistor for performing switching to provide a voltage signal to a gate of the current control thin film transistor in accordance with image data is provided for each pixel.
In the organic EL display device, electric characteristics of the thin film transistor in each pixel may change and vary over time, and light emitting characteristics of the organic EL element in each pixel may change and vary over time.
Further, for example, some of electronic devices such as a digital video camera, a mobile phone, and a personal computer are equipped with a movable (variable angle type) and pivotable display panel capable of freely changing attachment angle and direction with respect to the main body of the device and thereby changing the display form of the display panel to various kinds of display forms such as a horizontally reversed display and a vertically reversed display, and some of them are capable of displaying at a fast speed, e.g., double speed display operation when a motion picture is played back.
When the electronic device uses correction data for each pixel stored in a memory circuit to make correction in order to compensate change and variation of the electric characteristics of the thin film transistor in each pixel and change and variation of the light emitting characteristic of the light emitting element in each pixel as described above, it used to be difficult to perform the above correction operation using the correction data in a relatively short time when the display panel was operated at the fast speed or when the display panel was changed to various kinds of display forms.